Animal instrumentation

ABSTRACT

An approach to monitoring, evaluation, diagnosis, treatment or conditioning of animals such as horses does not require use of restrictive equipment such as treadmills or force plates and that can provide either or both of more or less immediate or continuous processing of data to perform the monitoring or diagnosis. One or more wireless sensors are attached to the animal, for example, to measure motion-related parameter associated with one or more parts of the animal. Sensor data is received from the sensors and processed to identify a characteristic of the motion of the animal, such as a quality of gait. The sensor data can also be used to avoid injury to the animal and/or the rider, and to verify the identity of an animal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/746,889, filed May 10, 2007, which is a divisional of U.S.application Ser. No. 11/136,201, filed May 24, 2005, which claims thebenefit of U.S. Provisional Application No. 60/573,863 filed on May 24,2004, which is incorporated herein by reference. This application isalso related to International Application No. PCT/US05/018022, alsotitled “Animal Instrumentation,” filed on May 24, 2005.

BACKGROUND

This document relates to animal instrumentation.

Objective evaluation and diagnosis of animals is difficult for a varietyof reasons. Most obviously, unlike humans, animals cannot easilycommunicate with a person who is evaluating, diagnosing, treating ortraining them. For example, a horse cannot communicate which limb orjoint hurts or in what way it hurts or under what condition it hurts.Another difficulty, especially for large or fast animals such as horses,is that it is difficult to obtain objective and quantitativemeasurements of physical or physiological parameters on an animal, thatare accurate, or reproducible, or reflect real-world conditions or areavailable in real-time. For example, it can be difficult and expensiveto bring a horse into a facility with suitable measurement equipment toobtain accurate and reproducible measurements, and these do notrepresent real-world conditions and may not be available in real time.As a consequence, evaluation and diagnosis and treatment andconditioning are typically based on subjective and qualitative judgmentsof veterinarians, trainers or riders.

An important area of evaluation and diagnosis relates to lameness inhorses. Competitive horses are valuable assets. Furthermore, they arephysically fragile and are particularly susceptible to lameness. Expertsestimate that at any one time at least 10% of all equine athletes areclearly lame or injured or out of condition in some way that preventsthem attaining peak performance, and many more have subtle or chronicconditions that are difficult to detect or need monitoring.

Therefore, it is desirable to apply effective evaluation and diagnosistechniques to diagnose injury, to prevent injury, to enable thetreatment of injury or to aid in recovery from injury in order toprotect their value. In addition, it is desirable to improve theeffectiveness of programs for training and conditioning. Once lamenessis discovered, lengthy rehabilitation is often necessary. Significanteffort and expense is expended on many competitive horses. Lamenesstemporarily or even permanently negates the benefit of such significantinvestment.

Detection and diagnosis of lameness in horses today is largely based onsubjective and qualitative evaluation. Typical techniques involveobservation to detect asymmetries in motion, gross evaluation of astationary animal such as by palpitation of limbs, and use of anestheticblocking of nerves to determine if lameness is alleviated, for example,by blocking pain from a particular joint. Note that in this lasttechnique, although the horse may appear less lame, the underlying causeof lameness may in fact cause further damage to the horse during theevaluation.

Modern medical and veterinary techniques can involve some objective andquantitative monitoring of physical and physiological parameters. Forexample, monitoring of physiological parameters (for example, an EKG)during treadmill-based exercise is a well-established diagnostictechnique for people. Treadmill-based techniques are also used foranimals such as horses, with notably increased difficulty associatedwith the size of the animal and the limited means of communication withthe animal. For example, a lengthy period of acclimatization and the useof tranquilizing drugs may be required.

In the veterinary domain, when objective measurements are sought,monitoring and diagnosis of accurate and reproducible physical andphysiological parameters has generally included the use oftreadmill-based techniques, video monitoring using optical markers totrack limb position, or the use of force plates upon which a horsesteps. These approaches do not necessarily reflect real-world conditionsor support continuous monitoring.

Ambulatory monitoring has been attempted using a sensor for accelerationor recording heart rate and respiratory sounds for large animals,including horses. In general, these various objective measurements areeither limited in the duration of the trial, or in the accuracy andreproducibility of the data, or performed for a limited set ofparameters at a time, such as using a single two-axis accelerometer at50 Hz for a few minutes, or a single sound sensor. In addition, they aretypically very costly.

Other types of systems provide assistance for subjective evaluation,such as facilitating mark-up of video captured using commerciallyavailable consumer camcorders and using this assisted subjective data asthe basis for analysis. These approaches have time resolution in therange of 50 Hz or 60 Hz (limited by the video frame rate) and a fewcentimeters in space (limited by video resolution), and generally lackof reproducibility because of the subjective assessment involved.

SUMMARY

In one aspect, in general, an approach to instrumentation and telemetryof physiological and physical parameters of an animal and itsenvironment has particular application to horses. This approach improvesthe effectiveness of one or more of evaluation, diagnosis, careconditioning or monitoring of animals because it does not require use ofrestrictive equipment such as treadmills or force plates, and it canprovide objective and quantitative data that is accurate andreproducible, and this data can be obtained under real-world conditions,for either or both of more or less real-time or continuous processing ofdata to perform the monitoring or diagnosis. That is, in such anapproach objective and quantitative data can be collected underreal-world conditions and this data can be processed and the informationcan be displayed in real-time.

In another aspect, in general, a method involves measuring acharacteristic of the motion of an animal and transmitting andprocessing and storing this information. One or more sensors areattached to the animal. These sensors include a sensor for measuring amotion-related parameter associated with a limb or other part of theanimal. Sensor data is received from the sensors and processed toidentify a characteristic of the motion of the animal and thisinformation can optionally be displayed.

In another aspect, in general, a method for avoiding injury to an animalmakes use of a number of sensors. Sensor signals are processed toidentify the actual or potential for the injury condition, and feedbackis provided to avoid the injury.

In another aspect, in general, a method for monitoring the treatment andrecovery of an animal is related to either or both of accelerating thetreatment and recovery or increasing the likelihood of a successfuloutcome. This method may be used to avoid bringing an animal back intocompetition or work before it is ready, or alternatively prolongingtreatment and recovery any longer than necessary.

In another aspect, in general, a method relates to monitoring andimproving the conditioning, training or preparation of an animal. Theconditioning or training may extend over a prolonged period, and theimprovement may involve changes in the approach or methods adopted. Forexample, if a horse is being trained and conditioned for an event, theimprovement may include selecting when and which event to enter orwhether or not to participate, or whether or not to continue training orhow to continue training. The preparation may also include the choice orapplication or configuration of equipment (for example shoeing a horseby a farrier, or choosing a particular configuration of tack).

In another aspect, in general, a method relates evaluating or monitoringthe potential performance of an animal. For example, this method caninclude evaluating the potential of a young or untrained animal, andthen updating the estimates of the potential performance over time asthe animal matures and undergoes training. The evaluation of potentialmay combine data from sensors with other data, such as measurements ofconformation.

In another aspect, in general, a method relates to evaluating ormonitoring the performance of the people involved in training orconditioning an animal or performing in competition, and improving theirperformance. For example, this can provide feedback to and guidance fora show-jumping rider to improve their performance or feedback to andguidance for a jockey riding a racehorse.

In another aspect, in general, a system for monitoring an animalincludes a sensor subsystem fixed to the animal, including at least onesensor for measuring a physical parameter associated with at least onelimb or the animal. A computing subsystem is used for real-timeprocessing of data provided by the sensor subsystem. A communicationsubsystem couples the sensor subsystem and the computing subsystem andis for passing sensor data from the sensor subsystem to the processingsubsystem.

In another aspect, in general, a system for monitoring an animalincludes a communication hub for attaching to an animal. Thecommunication hub includes a receiver for accepting sensor data fromsensors attached to the animal and a transmitter for providing databased on the accepted sensor data. The system also includes a set ofsensors, each including a transmitter for providing sensor data to thehub. The communication hub is configurable for receiving sensor datafrom a selection of the set of sensors attached to the animal.

Aspects of the invention can include one or more of the followingfeatures.

Multiple sensors are attached to the animal, each sensor providing atleast some of the sensor data. The sensors can each measure amotion-related parameter associated with a different limb or part of theanimal. The sensors can each measure a different motion-relatedparameter associated with a single limb of the animal, such as themovement of different portions of the limb.

The sensors monitoring the physical or physiological parameters of theanimal include any set of one or more of: an inertial sensor to measurelinear or rotational position, motion or acceleration; a force, strainor pressure sensor; a muscle, nerve or connective tissue activitysensor; a respiration sensor; a cardiac sensor; a blood oxygen sensor;an audio sensor; a visual sensor, such as an endoscope; or a temperaturesensor. The sensors are optionally removably attached to the animal

In addition, the system can include additional sensors that monitor theenvironment, including time and location, and temperature, humidity andatmospheric pressure.

The sensor data can include normal speed or high speed, standarddefinition or high definition video monitoring and recording.

The sensor data from a number of different sensors can be synchronized,so that users can assess multiple parameters at the same time, withreference to a common timeline. The processing of the received sensordata is in a real time mode, or alternatively in a batch mode. Thesensor data or analyses of the sensor data and related data can bedisplayed at any speed, from a static snapshot, through interval byinterval, slow motion, real-speed and speeded up.

The sensor data is collected during a normal activity of the animal, forexample, during regular exercise, training or an athletic event. Thereceived sensor data can be processed during the normal activity.

Identifying the characteristic of the motion includes identifying aquality of gait of the animal. The quality of the gait can include aphysical parameter of the gait, such as stride length and timing, thetiming of stance and swing phases, the relative timing and magnitude oflinear or angular motion of limbs or other parts of the animal, such asthe head. The quality of gait can include a lameness exhibited in thegait of the animal.

Processing the received sensor data includes identifying an injurycondition based on the received signals, such as an actual injury or apredisposition to an injury.

The sensor data or other information can be passed over a wirelessnetwork local to the animal, and the sensor data or other informationcan be also passed over a wireless link to a station or server remotefrom the animal. For example, sensors for motion can typically use a lowpower wireless link for the short distance from the sensor to the hub,and then a higher power link for the longer distance from the hub to thereceiving station, or server while the horse is in motion.

The sensor module can also include a small amount of memory to act as abuffer for storage of data, before it is transmitted to the hub. The hubcan include a large amount of memory, sufficient to store data forseveral hours or even days, to allow extended monitoring when it is notfeasible or desirable to transmit data from the hub to a station orserver.

The sensor data can be secured, for example through using encryptiontechniques. This ensures that it cannot be intercepted or tampered with.

The system can authenticate the data that is being provided on the basisof time, based upon an internal reference clock or an external referenceclock. It can authenticate the data as being provided at a certainlocation on the basis of internal references, such as inertialmeasurements, or through an external reference such as the GlobalPosition System.

The system can include a method for authenticating the identity ofanimal involved in providing the data. For example, it may recognize anidentifier associated with the animal, such as a radio frequency IDdevice, or genetic information. Alternatively, it can authenticateidentity by establishing a chain of verification in which a trustedparty authenticates the identity of the animal at the outset, andinformation gathered from sensors is then used to verify the physicalsignature of the animal, from the pattern of physical or physiologicalinformation such as motion.

This can include capturing visual data, photos or video, at the sametime as physical data, and associating the information, so that it canbe verified that the photos or video were taken at the same time and inthe same place, and that the timing of the events in photos or videomatches the sensor measurements.

The system for the storage, processing and display of information can beconfigurable and modular. The design rules for the partitioning offunctionality into modules, and the interfaces between the modules canbe clear and stable, so that the development of each module can bedistributed and take place independently. This may include users orthird parties developing modules. This enables the system to be adaptedto a wide range of diverse applications.

The system allows information to be linked with or associated with otherrelevant information from the evaluation, diagnosis, care, conditioningor monitoring. For example, this includes notes or records provided byusers or others, such as other diagnostic measurements or images orrecords. This also supports pattern recognition, by enabling thedetection of linkages between quantitative and objective data providedby this system and the associated conditions or outcomes.

The system can allow remote monitoring of data in real-time or batchmode, so that a user who is not present can conduct or contribute toevaluation, diagnosis, care and conditioning. As part of this, thesystem can enable observations at multiple locations to be synchronizedor coordinated, so that users can look at the same information at thesame time.

Aspects of the invention can include one or more of the followingadvantages.

By allowing instrumentation without use of restrictive equipment (suchas a treadmill or a force plate) information that is more representativeof real-life condition of the animal may be obtained. For example,information related to a horse's physiological condition or physicalperformance can be obtained during low-stress conditions or during acompetitive equestrian event.

By allowing instrumentation without the need for further subsequentoff-line or batch processing of the data, such as analysis of videosignals, real-time monitoring of the data may provide immediatefeedback, which can be used to more quickly detect conditions and totake appropriate action.

Another advantage of instrumentation without use of restrictiveequipment relates to cost. Use of specialized facilities for largeanimals, such as large animal treadmills, high speed video equipment orforce plates, can be costly both for use of those facilities and fortransporting the animal to such a facility. Use of relativelyinexpensive equipment that can be attached and removed easily from theanimal can greatly reduce cost and make such instrumentation availableto a larger population of animals.

The instrumentation approach can be non-invasive. In particular,detailed evaluation and diagnosis of lameness without necessitating useof nerve blocking anesthetics has the advantage that the horse does notrisk further physical damage during the evaluation procedure. In asuccessful application of the nerve blocking approach, if the limb orjoint causing pain to the horse is blocked then the horse appears not tobe lame or less lame. But because the horse does not experience thediscomfort, further physical damage can occur while the anesthetic isactive through physical activity that the anaesthetized horse would haveavoided.

Availability of either or both of objective or quantitative informationabout an animal provides additional methods of diagnosis and assessmentof training, conditioning or rehabilitation programs over methods basedon subjective or qualitative information. For example, rather thanrelying on subjective or on qualitative information, for example,obtained by viewing the animal, objective and quantitative measurementsthat are accurate and reproducible can be used to detect subtleconditions, which are not readily apparent either because the size ofthe change in motion or in the pattern of motion is small or because thecondition only becomes apparent when the horse is moving faster, attrot, canter or gallop.

In addition, by storing historical data for an animal, comparisons canbe made over time of trend data (that is longitudinal comparisons), forexample to assess progress in a conditioning or rehabilitation program.Furthermore, comparisons can be made among different animals ofpopulation data (that is horizontal comparisons), for example, tocompare different animals' capabilities or their progress withequivalent training or recovery programs.

Information about a population of animals over a period of time andassociated information such as evaluations, diagnoses, care orconditioning regimes enable pattern recognition, such as throughstatistical analysis or inference. This can assist or accelerate some orall of evaluation or diagnosis, providing closed-loop care. This patternrecognition can be automated, so that the selection of algorithms andthe analysis of information do not require further action orintervention. This pattern recognition and feedback can includeproviding feedback to someone evaluating, caring for or using the horsein real-time. The system can provide automatic pattern recognition withfeedback in real-time, for example to provide a visual or audible alertto a rider of a lameness condition while riding the horse.

Use of wireless sensors, such as small lightweight wireless sensors, canimprove ease of use through easy attachment and removal of sensors froman animal without requiring the attachment of wires to collect sensordata. Such wireless communication may provide less restriction onmovement than wired approaches. In addition, the wireless approach mayprovide increased robustness and reliability by removing a point offailure of a wired link.

Sensor components and radio components are integrated in a robustpackage that can withstand environment and shock/pressure conditions.This package can vary the transmission rate to minimize powerconsumption. It can include automatic calibration to compensate forgain, rates, offsets or drifts. This automatic calibration can be basedon measurements from a single sensor package, or on results frommultiple sensor packages, or on results from multiple tests and multipleanimals. The power for this package can come partially or completely byscavenging from the motion of the animal. For example, in a horse thepower can come from piezo-electric methods using vibration when thehorseshoe impacts the ground, or electro-magnetic methods when the legis in motion.

A communication hub on the animal, for example, attached to the saddleof a horse (for example, in a weight pocket) or carried by the rider,may provide a way of improving communication between sensors and aremote station. For example, rather than each sensor necessarily beingable to transmit a wireless signal to the remote station, the hub canaggregate the data and then transmit it to the remote station. As anexample, a hub may receive sensor data over relatively low-powershort-range wireless links, and then transmit the aggregated data to aremote station using a wireless link that has relatively higher-power orlonger range.

A configurable and modular system for instrumentation and telemetry canbe adapted for a wide variety of types and combinations of sensors.Furthermore, an automatic configuration of the system (for example of ahub) can increase the ease with which an animal is instrumented byremoving the requirement that a user configure the system. For example,depending on the sensors that are present, the system can configureitself to communicate with each of the available sensors. For example,depending on the sensors that are providing signals, the system canconfigure itself to process the provided signals. For example, differentprocessing algorithms can be selected automatically depending on thesensors that are available.

This self-configuration approach can also provide robustness to loss ofsensors in real-life situations. For example, a system may be configuredto analyze gait based on multiple accelerometers on limbs of an animal.If one of the accelerometers becomes unavailable because it is damaged,or starts transmitting erroneous data because it has become dislodged,the system may be able to reconfigure itself to use the remainingsensors.

Security and authenticity of data collected from an animal provides anumber of commercial advantages, for example, related to avoidance offraud in the sale of animals. The secure data can be used foridentification purposes, thereby reducing a possibility an imposter toan animal being sold. Furthermore, longer-term monitoring of physicaland physiological parameters can provide advantages in insuranceunderwriting by being able to identify material conditions.

A configurable and modular system for processing, storage and displaycan be adapted for a wide variety of applications. Furthermore, anautomatic configuration of the processing, storage and display systemcan increase the ease of evaluation, diagnosis or monitoring by removingthe requirement that a user configure this system. For example,depending on the information that is available, the system can configureitself to use algorithms appropriate to the application, and to displaythe results in a format appropriate to the application.

Furthermore, a modular system for storage, processing or display thathas clear and well-defined interfaces for processing modules and fordisplay modules of the information allows the development and deploymentof these modules to be widely distributed. Users and third parties cancontribute significant innovations in processing or pattern recognitionor visualization, appropriate for a wide range of diverse applications.

The ability to have both local and remote access enables the optimumcombination of individuals to evaluate, diagnose, care or monitor ananimal, depending on the animal and the application. For example, if ananimal is at a location remote from the people who typically providecare, they can contribute in conjunction with someone who is presentwith the animal. For example, in another application a local provider ofcare can obtain support from another practitioner with specialistexpertise relevant to the animal or application.

The linkage to other information supports a complete cycle of closedloop care, in which quantitative and objective data that is accurate andreproducible is used in conjunction with other information, such assubjective observations, other diagnostic measurements or images, andtraining or veterinary records relating of the animals' condition or theoutcome of care or conditioning regimes.

Other features and advantages of the invention are apparent from thefollowing description, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of an equine instrumentation, telemetryand informatics system.

FIGS. 2A-B are block diagrams of the instrumentation, telemetry andinformatics system.

DESCRIPTION

Referring to FIG. 1, an instrumentation and telemetry system 100 is usedto collect and process information regarding physical and physiologicalparameters of a horse 101 and optionally of the horse's rider 102 andits environment. Before beginning monitoring or during the course ofongoing longer-term monitoring, a number of sensors 110 are attached tothe horse. These sensors provide data to a hub 120, which is alsoattached to the horse or is alternatively carried by the rider 102 orlocated nearby, such as on a trailer. The hub provides some of thecommunication or processing or storage or display functionality for thesystem. Information from the sensors is received over communicationlinks 115 at the hub 120, where it may be stored, and optionallytransmitted immediately or subsequently over a communication link 125 toa remote server 130, which is typically stationary. Optionally,information is also transmitted to a display 122 or other audio, tactileor visual output device (for example a heads up eyeglass display,colored LEDs, or similar device) to provide feedback to the rider 102 ofthe horse.

The server 130 includes one or more workstations 240 for recording,processing and transmitting information generated from the sensor data,each of which has a user interface for report/display 244 andinput/controls 246 (such as a terminal or a workstation with a display)through which a user can examine the information, and optionally one ormore data servers 250, each of which stores animal data 252 andauthentication data specifying access rights to this information.Computing resources for processing data from the sensors are hosted atthe hub 120 and/or at the server 130. For example, the hub may hostsignal conditioning and, data reduction functions and data buffering,while the server may host information storage and analysis functions.

In a preferred mode of operation, the horse is not necessarily confinedduring the collection of data, although the system might be used inconfined situations while still providing advantages over other systems.By not requiring that the horse be confined, the data can be collectedduring a normal activity. By normal activity, we mean activity that thehorse would generally have undertaken had the collection of data notbeen desired or required. Such normal activities can range include,without limitation, roaming freely in a paddock, to routine exercise, totraining for a competitive event (such as jumping or racing), to oractual competition.

A wide variety of sensors 110 can be used with the system in anyparticular monitoring situation. Some sensors relate to data collectionfor the analysis of gait, for example, to detect actual or propensityfor lameness. Such sensors include inertial sensors that are attached tothe limbs. Inertial sensors include linear and rotational accelerometersor gyroscopes. The information from such sensors is used for functionssuch as estimating limb positions or motion as a function of time ordirectly measuring asymmetric asymmetry of motion. Other sensors relatedto gait include strain, pressure or force sensors embedded in the horseshoes, sensors measuring joint movement or position, and physiologicalsensors that measure aspects such as nerve signals, muscle signals(electromyography), and muscle and tendon position or motion. Asdiscussed further below, additional sensors, which are not necessarilydirectly related to gait analysis, can also be used.

In general, multiple sensors are used to generate concurrent recording,for example, from one or more of multiple limbs or from other parts ofthe horse such as the body, neck or head. For example, one or more ofinertial sensors or strain or pressure sensors attached to multiple legsof the horse as well as to the horse's head or neck provide data thatcan be combined to analyze the gait of the horse. In addition, multiplesensors can be used on one limb, for example to track the motion ofindividual segments of the limb.

It is desirable to minimize the restrictive nature of theinstrumentation applied to the horse. For example, small, lightweightlow-power devices are used, and wireless communication is used betweenthe sensors and the hub. For example, the hub and each of the sensorsincludes a radio and a local (to the horse) wireless data network basedon the Bluetooth standard can be used to communicate on one or moreradio channels between the sensors and the hub. Other wireless approachcan alternatively be used, for example, based on low-power ad-hoc datanetworks such as using the Zigbee or IEEE 802.15.4 standards), which mayallow data to pass between the sensor and the hub in one or multiplehops (for example via other sensors acting as forwarding nodes). In somecases, wired connections may be preferable (such as USB, or Firewire),for example, if such a wire does not restrict motion, and thecharacteristics (such as bandwidth, power consumption, size, or weight)of the sensor are preferable if it does not require wirelessconnectivity.

Some devices may optionally function partially or completely withoutbatteries relying only on parasitic energy from the motion of the horse,for example, using piezo-electric generators in horseshoes orelectro-magnetic generators on a moving limb portion. In order toconserve power and extend battery life, some sensors can vary theirtransmission data rates based on their sensed signals, for exampleproviding higher data rates when they measure more rapid changes. Forexample, an acceleration sensor on a hoof may transmit at a higher rateduring a gallop than at a walk, and may transmit at different rates atdifferent phases in each stride. The timing of and rate of datatransmission may be determined by the sensor module, or by the hub, orby negotiation between them.

Communication between the hub 120 and the server 130 also uses awireless data channel. For example, the hub can include an additionalradio for communicating with the server, with the other radio being usedto communicate with the sensors. A number of alternative types of radiochannels can be used. For example, a dedicated point-to-point radio linkmay be used. A wireless data network can also be used, for example,based on a wireless Ethernet (such as 802.11a, 802.11b or 802.11g)standard. Using a wireless data network, multiple wireless access pointscan provide connectivity between the hub and the server over arelatively wide area, for example, from inside a stable to distantlocations in a paddock or on a race course or a show jumping arena or adressage ring or an eventing cross-country course. Wide area wirelesscommunication can also be used, for example, based on cellular orsatellite or wide area broadband wireless technology, such as GSM/GPRSor W-CDMA or CDMA1X or FLASH-OFDM or IEEE 802.16 or 802.20 dataservices. Using a wide area communication approach can provide globalcoverage for the monitoring, for example, allowing monitoring of a horsein transit to a distant location, or during training or competing atthat distant location.

Security of the data may be desirable for a number of reasons, includingprivacy of the data collected about a horse (that is preventinginterception of or interference with the transmitted data) andauthentication of the data that is to guarantee that the collected datawas truly collected and not tampered with or altered in some way. Oneaspect of the system that provides security is encryption of thewireless link 125 that couples the hub 120 and the server 130.Similarly, wireless links 115 between the sensors 110 and the hub 120are also optionally encrypted, although because of generally lower powerand the limited nature of the data the threat of interception may be aless serious concern on these links. For authentication, data sent fromthe hub can be cryptographically signed to guarantee that the data wasgenerated by the particular hub or by particular sensors on the horse.

Additional contextual data, such as date and time-of-day and positiondata may be included in the data sent to the server to time and locationstamp the data and for use in further cryptographic authenticationand/or verification of the data. For example, the hub can optionallyinclude a GPS receiver that is used to determine the time and locationdata.

In addition to sensors such as accelerometers and strain or force orpressure sensors, which generally relate to collection of parametersthat can be used to analyze the gait of a horse, the system can be usedto collect and analyze other signals including physiological parametersand characteristics of the environment. For example, cardiovascularsignals such as heart rate, blood oxygen level, and blood pressure canbe collected and sent through the hub to the server. Similarly, audio orvideo measurements, such as recording of respiratory sounds (or airpressure) or endoscopic video can be collected. Also, signals related tothe rider may be collected and used in conjunction with signals relatedto the horse. For example, signals that relate to the rider's position,stance, pressure on reigns, stirrups, or through their legs, or otheractivity can be collected, as can physiological signals such as therider's heart rate or breathing rate.

In addition, sensor that measure environmental conditions, such as airtemperature, humidity and pressure, can provide environmental data thatcan be collected and correlated with performance or physiological data.In particular, the signals can be associated with high speed or normalspeed video monitoring of the horse.

The system can be used in a number of different applications. A firstapplication relates to gait analysis. For example, sensors aretemporarily attached to a horse and data collected for the purpose ofevaluation or diagnosis, for example, for a duration of less than a day(such as a normal exercise regimen of approximately an hour). One typeof analysis relates to detection of asymmetry in a horse's gait. Forexample, if motion or hoof pressure is asymmetrical (that is, from sideto side), lameness may be indicated. In addition, pattern classificationapproaches, for example, based on statistical data collected from apopulation of other lame and sound horses, (or prior data collection forthe same or another single horse) may be used for diagnosis.

Gait analysis can include a number of alternative types of processing ofsensor signals, for example, depending on the sensor signal actuallyavailable and the information that is desired. The parameters that canbe derived from sensor measurements include the height and length of thefoot flight arc, stride length and rate, alterations in the foot flight,timing and distance of phases of the stride, the magnitude and timing ofjoint angles, extension of the limbs, range of motion, gluteal rise andfall, relative force and pressure on different hooves. The analysis caninclude related movements such as movement of the head up or down orfrom side to side to compensate for lameness, or motion alteration whenmoving in an arc in one direction or the other direction.

Part of the gait analysis can involve categorization of the gait inwhich the horse is moving, such as walk, trot, canter and gallop, orcollected, working, medium and extended gaits. This categorization maybe used on its own, or can be used in further data analysis, forexample, to trigger analysis that is particular to a gait. For example,a certain type of detailed analysis may be applicable only at a trot,and the classification may be used to trigger the analysis. The analysismay be used to determine subtle lameness, as opposed to a binaryclassification of lame versus not lame.

Another part of gait analysis relates to measurement of signals relatedto the quality of motion of a horse's gait. The quality of motionincludes characteristics which may depend on detailed aspects of limbmotion, such as the trajectory of limb segments (such as “paddling,”straight versus swaying from side to side, pointing and “flipping” ofthe hoof and so on), timing of various stages in the gait (such as dwelltime, “hang time” immediately before the hoof hits the ground, and soon) and smoothness of the overall motion. Quantities characterizing thequality of motion of a horse's gait are derived from the underlyingsensor signals, either in real time at the hub or on the server, or aspart of a later analysis of sensor data.

Another application also relates to gait analysis, but the collectionperiod may be longer than a day. For example, the sensors may be appliedto the horse (including for example using instrumented horse shoes) andthe data collected over a period of days, weeks, or longer. In such anapproach, changes over time can be used to detect or predict conditionssuch as lameness. The extended period is not necessarily continuous. Forexample, the sensors may be applied to the horse during a regulartraining period each day. Alternatively, the sensors may be applied andkept on the horse continuously.

Another application involves a closed-loop diagnostic procedure. In thisapplication, sensors are attached to the animal, and a first set ofmeasurements and associated analysis are performed. Using a differentialdiagnosis or decision-tree approach (for example, based on expertknowledge or derived from empirical data), the results of the firstanalysis determine the next set of measurements to perform. It may benecessary to perform a different set of motions, or to reposition thesensors, or to use different sensors for each iteration. The diagnosisor decision process may be computer aided, for example, encoding thelogic for which measurements to perform based on results of analysis inprevious iterations.

One way of providing the data from the sensors to a user is with agraphical interface using tabular or graph representations of the data.The interface optionally permits a user to zoom in or drill down onparticular displayed data to view more detailed information.

Extended monitoring, or repeated monitoring at time intervals (forexample weekly) can also be used to identify trends. For example, datafor a particular horse is stored at a server, and automated orcomputer-aided techniques are used to analyze the stored data. In onetype of analysis, statistical deviation from past data is used toidentify unusual events or trends, which could be associated with aninjury. In another type of analysis, comparison is made between the datafor one horse and data for another horse or for a population of horses.

In another application, the sensor data is used to track changes. Oneaspect of such tracking relates to tracking conditioning that is fitnessand muscle strength of a horse based on quantitative parameters. Forexample, the system can provide information that is used to determinewhich muscle groups require additional emphasis in training. Anotheraspect of such tracking relates to rehabilitation or convalescence of ahorse after an injury. For example, the quantitative data can be used todetermine a best course of training during a recovery period after aninjury.

A related application involves monitoring progress during recovery froman injury. Periodically (or even continuously) during care after aninjury, the animal is monitored and characteristics, such as gait orperformance characteristics, are recorded. These characteristics arethen used to determine the recovery progress of the animal and/or todetermine the type or amount of work the animal should perform. Progresscan be measured by predetermined thresholds, and can be based on acomparison of previously monitored progress during recovery fromprevious injuries, for example, from a population of similar animalswith similar injuries.

A related application involves evaluating or monitoring the training orthe conditioning or the preparation of an animal. For example, data forthe horse is used to determine what is the optimal training orconditioning regime. For example, this data is used to determine theeffects of different approaches to shoeing of a horse, and to optimizethe choice and fitting of shoes.

Another application relates to assessment of athletic performance orpotential athletic performance of a horse. In such an application,rather that diagnosing an injury, physical parameters, for example,related to speed, endurance, jumping ability, and so on are collectedusing the system. This data may be used in combination with otherobjective measurements (for example conformation measurements orradiographs or physical examination) or subjective assessments. Forexample, objective and quantitative data about the physical,physiological and performance characteristics of top competitive horsescan be used to provide an objective benchmark or target set ofparameters, then over time the trends in the development of a cohort ofhorses towards these benchmark characteristics can be used to identifywhat the salient characteristics of younger or untrained horses are thatcorrespond well with subsequent high levels of competitive performancewhen older or well-trained. For example, this information could thenprovide an objective basis for the assessment of potential purchases,and used to maximize the return on investment. This may apply toracehorses, as well as to showjumpers and other events.

A related application relates to assessment of the performance of peopleassociated with the horse, and improving their performance. For example,this may involve providing a rider with quantitative feedback on howthey are riding.

Another area relates to identification of a horse, for example, toprevent fraud in sale of the horse. Certain physical parameters, such asdetailed gait patterns may be individual to a horse and not easymimicked. Previously recorded and authenticated data for a particularhorse can be used to determine later whether another horse is that samehorse. For example, a statistical test can determine whether the newdata for the horse is characteristic to that horse (for example, thereis a low statistical probability that the data comes from a differenthorse), and discriminant analysis using data from other horses canidentify derived features from the sensor measurements that provide highinformation related to the horse's identity.

Another fraud-related application is applicable to reduction ofinsurance fraud. For example, collection of quantitative data might be acondition of obtaining health-related insurance for a horse. Aninsurance underwriter could require that such collection of data span anextended continuous period, thereby making it difficult to hide certainconditions, for example, by using short acting medications.

Another application relates to safety, for example, during an equestrianevent. Some events can be very dangerous for both the horse and therider. In this application, relatively unobtrusive sensors are attachedto the horse for the competition. The sensor data is monitoredcontinuously during the event. Based on human monitoring or on anautomated signal-processing algorithm, each horse in the event istracked and if a high likelihood of injury is detected, the rider can bepulled from the course.

Other applications relate to long-term monitoring, for example, duringthe course of a pregnancy in which gynecological and/or fetal signalsare monitored. In addition, monitoring can be targeted at the detectionof colic in otherwise healthy animals.

The system also has application in situations in which the animal isconfined, for example in a stall, in a vehicle while being transportedor on a treadmill. In such an application, the hub is not necessarilyattached to the horse and can be in a stationary location, possiblyco-located or even hosted in the server (for example as a peripheralcard or device in the server computer). Even though the animal isconfined, the lack of wired connections between sensors on the horse andthe rest of the system facilitates and simplifies the diagnostic ormonitoring procedure.

In view of the wide variety of sensor types and algorithms that may beemployed, in a preferred version of the system, a self-configurationfeature enables parts of the system to be automatically configured basedon the sensor data that is available.

One type of automatic configuration relates to automatic detection ofthe sensor data that is available. For example, various sensors may beattached to the horse and the hub automatically determines what data isavailable. The hub may also configure local processing algorithms, forexample, to estimate gait features based on whatever sensor data isavailable. For example, if hoof pressure data is available, a differentsignal-processing algorithm may be employed than if only inertial datais available from limb extremities, and yet another algorithm may beemployed when both pressure and inertial measurements are available.

The identification of the type of sensor, as the basis forauto-configuration of the system, can include the use of publicstandards, such as the IEEE 1451.4 standard for smart transducers thatare very small or that are part of a distributed array.

The sensors may further identify themselves, for example, providingsensor parameters to the hub, which can be used to calibrate the data.Further, the system may automatically determine where on a horse thesensors are attached. For example, rather than having to identify whichaccelerometer sensor is attached on each leg of the horse, the systemcan automatically determine which signal is from which leg. Furthermore,link segment modeling may be used for analysis as well as automaticconfiguration. For example, based on a model of a horse's limbs, theparticular limb segment to which each sensor is attached, as well as thelocation on that limb segment can be determined automatically. Forexample, the rider may indicate to the system that the horse is in acanter on a right lead, and a model of such a gait is then used toautomatically calibrate the sensor locations. Sensor measurementparameters such as gains, offsets, rates or drift, and so on can also beautomatically determined from measurements from the sensors.

Sensors can be of various types. For example, some sensors are“off-the-shelf” digital or analog devices using industry standardinterfaces. For example, a USB-based or Bluetooth-based microphone orcamera might be such a device. Alternatively, a sensor might use acommon analog interface, and be connected directly to a compatibleanalog interface on a hub or sensor module. Other sensors arespecialized devices, but can emulate standard devices. For example, anendoscope might have a USB interface that is the same as a standard USBvideo camera. Other devices may have non-standard interfaces, forexample, using low-power radio networking communication. Finally, forsome devices, the hub emulates a proprietary receiver, for example toreceive heart-rate measurements.

Other types of automatic configuration may relate to automatic detectionof the particular horse to which the sensors are attached. As anexample, RFID technology can be used to identify the horse using a tagattached to the horse. As a related benefit of such technology, RFIDdata or related data can be used for authentication of the data.

The system may include automatic calibration of the sensors. Forexample, the data from a sensor may be used to calibrate for andcompensate for gain, rates, offsets and drifts. Alternatively, the datafrom a number of sensors may be combined as the basis for thiscalibration, or this data from a particular horse and time and place maybe combined with additional information from other trials or otherhorses.

Referring to FIG. 2A, an embodiment of the system includes sensors 110and one or more hubs 120 that are local to the horse. The sensors 110can include sensors for measuring characteristics of the animal (“animalsensors”) 210, including gait-related sensors (such as accelerometers,pressure sensors, etc.), cardiovascular sensors, respiratory sensors,gastro-intestinal sensors, and gynae/foetal sensors. Rider sensors 220provide measurements related to the riders position, physiologicalstate, etc. Environment sensors 219 provide measurements related to thetemperature, humidity, etc. In addition, a context module 236, which caninclude a GPS receiver to determine the location of the horse and therecording time and can include a RFID reader to determine the identityof the horse (or the rider) can provide data to the hub 120.

The hub 120 includes a sensor communication interface 222 that providesa communication path to the sensors 110. A processor 224 is coupled tothe sensor communication interface. The processor executes instructions(such as programs, procedures, scripts, and so on) that are stored in aprocessing instruction storage 230. The instructions can be permanentlyresident in the hub, for example in a read-only memory, loaded from amachine-readable medium, or downloaded over a communication link such asfrom a server 130. The hub also includes a data storage 228 that is usedto hold sensor data, for example, as it is processed in the hub or as itis buffered for transmission to a server. A user interface 232 in thehub provides an interface to user display/controls 234. A servercommunication interface 226 provides a data communication path to aserver 130.

Note that the hub is not necessarily attached to the horse, for example,on the saddle or in a weight pocket. In one alternative, the hub iscarried by the rider. In another alternative, particularly when thehorse is confined, the hub is in the proximity of the horse, forexample, housed on a stall or in a trailer or near a pallet, rather thanbeing carried by the horse. The hub can include special-purposehardware, and can be hosted in a more generally available platform suchas a personal digital assistant (PDA) or a cellular telephone (forexample, acting as a data gateway to pass Bluetooth based sensor signalsonto a GSM data network).

A hub 120 can be associated with a horse for an extended period, forexample, being attached and removed from the horse as needed. Atdifferent times, it may communicate with different servers 130.Authentication techniques are used to prevent the hub from disclosinginformation to unauthorized servers, or to protect the data on a commonserver.

Referring to FIG. 2B, remote from the horse, a server 130 can includeone or more workstations 240, each of which includes a data storage fordata 242 and a user interface for report/display 244 and input/controls246. Another computer can serve as a data server 250 and also includes adata storage 252. For example, the data server may be a centralizedcomputer that serves as a secure repository for data that may becollected from different horses and at various venues each of which isserved by a different workstation 240, or that may be retained forvarious purposes such as veterinary care or fraud prevention. The dataserver includes can include a secure data storage 252 with associatedauthentication data 254. The data server may include local userinterfaces 258 and remote user interfaces 260 for viewing the data andcontrolling the system. The interfaces for displaying the data may bemodular and configurable, capable of working from static pictures of aparticular instant in time through faster than real-time, at differentlevels of aggregation and abstraction, from raw data through. Varioustypes of graph or animation displays can be generated from the data. Forexample, sensor data or derived quantities can be displayed orvisualized in graphical or numerical tabular form. Animations can alsobe generated from the data, for example, showing some or all of theanimal in a schematic (for example, as a stick figure) or a realisticanimation. Data from various sources can be synchronized and displayedtogether, for example, enabling synchronized display of actual videorecordings of the animal and data derived from sensor measurements.Similar synchronization can be applied to other imaging techniquesincluding MRI and ultrasound imaging.

In addition, remote monitoring and display of this information ispossible, through wide area communication networks, such as theInternet, enabling tele-veterinary services, or an owner to monitor anexercise session, training regimen or competition.

This data may be associated with other data, such as structured orfree-form notes, or other diagnostic images or measurements, provided bythe rider, trainer or veterinarian.

Alternative versions of the system are applicable to different animalsthan horses. Some of the techniques are particularly related to gaitanalysis of quadrupeds, but in general, the approaches are not limitedin this way. Indeed, some applications of the system are applicable tomonitoring of humans, for example, during athletic events.

A number of alternative system architectures are possible within thegeneral approach described above. Alternative communication technologiesare discussed above. In addition, the arrangement of the modules can bedifferent. For example, a hub may not be used if the sensors cancommunicate directly to the server. In such a case, all the processingof the data occurs at the server. In another alternative, all theprocessing occurs in real time at the hub and the server is not neededfor real-time processing. For example, the server may provide arepository for data that is recorded on the hub and periodicallytransferred to the server.

Various different types of authentication and related techniques can beused in the system. These include approaches for maintaining privacy ofdata, ensuring that data has not been tampered with, and providing thirdparty verification regarding the time and place of collection andpossibly the identify of the animal that generated the data.

Authentication can be based on a chain of trust, for example, based on achain of cryptographic certificates used to sign data. For example, datacan be certified as having been collected through a particular hub, andthe hub can be certified as having been associated with a particularhorse by an entity (or chain of entities) that are trusted. Furtherauthentication can be based on continuity of measurement and continuityof characteristic features of motion, so that once a hub is associatedwith an animal, there can be some level of certainty that measurementsfrom that hub remain from the same animal

The hub can be implemented using a programmable processor and under thecontrol of software that is stored on a medium such as a magnetic diskor solid-state memory in the hub. The programmable processor can be aspecial-purpose processor or can be a general-purpose processor. The hubcan use a standard operating system (such as Linux). The software forthe hub can be distributed on media such as optical disks, or can bedistributed over a data network (i.e., as a propagated signal) anddownloaded into the hub. The server computers can also be controlled bysoftware that is executed on a programmable processor, with the softwarebeing stored on a medium, which would typically include a magnetic disk.

It is to be understood that the foregoing description is intended toillustrate and not to limit the scope of the invention, which is definedby the scope of the appended claims. Other embodiments are within thescope of the following claims.

1. A method comprising: receiving first data from one or more sensorsattached to an animal, the sensors including a sensor configured tomeasure a parameter associated with motion of a part of the animal,wherein the parameter associated with motion of a part of the animalincludes a parameter selected from the group consisting of an arc ortrajectory of a limb or a portion of a limb, a magnitude and timing ofjoint angles, a flexion or extension of a limb or of a portion of alimb, and a range of limb motion; determining an attribute of motion ofthe animal based on the received first data; comparing the determinedattribute of motion with a prior attribute of motion determined based onsecond data previously received from one or more sensors attached to theanimal; and evaluating a change in a condition of the animal on thebasis of the comparison of the attributes of motion.
 2. The method ofclaim 1, wherein the attribute of motion includes a trajectory attributeof motion.
 3. The method of claim 2, wherein the trajectory attribute ofmotion includes a quality of a gait of the animal.
 4. The method ofclaim 3, wherein the trajectory attribute of motion includes atrajectory of a limb of the animal.
 5. The method of claim 1, whereinevaluating a change in the condition of the animal includes identifyingan injury or a possible injury to the animal.
 6. The method of claim 1,wherein evaluating a change in the condition of the animal includesdetermining at least one of a level of fitness of the animal and astrength of a muscle of the animal.
 7. The method of claim 1, furthercomprising assessing a degree of rehabilitation of an injury to theanimal on the basis of the evaluated change in the condition of theanimal.
 8. The method of claim 1, further comprising providing arecommendation for a treatment for an injury to the animal on the basisof the evaluated change in the condition of the animal.
 9. The method ofclaim 1, further comprising assessing a progress by the animal in aconditioning program on the basis of the evaluated change in thecondition of the animal.
 10. The method of claim 1, further comprisingproviding a recommendation for a training program for the animal on thebasis of the evaluated change in the condition of the animal.
 11. Themethod of claim 1, further comprising: receiving the second data; anddetermining the prior attribute of motion based on the received seconddata.
 12. The method of claim 1, wherein the sensors include a sensorconfigured to measure a physiological parameter of the animal.
 13. Themethod of claim 12, further comprising: comparing the measuredphysiological parameter with a prior physiological parameter; andevaluating the change in the condition of the animal further on thebasis of the comparison of the physiological parameters.
 14. The methodof claim 1, wherein the parameter associated with motion of a part ofthe animal includes a parameter selected from the group consisting of:stride length; stride rate; height and length of a foot flight arc;alterations in foot flight; magnitude and timing of joint angles;extension of a limb; range of limb motion; and relative force andpressure on different hooves.
 15. The method of claim 14, wherein theparameter associated with motion of a part of the animal includes aparameter selected from the group consisting of: stride length; striderate; and height and length of a foot flight arc.
 16. The method ofclaim 14, wherein the parameter associated with motion of a part of theanimal includes a parameter selected from the group consisting of:alterations in foot flight; magnitude and timing of joint angles;extension of a limb; range of limb motion; and relative force andpressure on different hooves.
 17. The method of claim 1, wherein theparameter associated with motion of a part of the animal includes aparameter associated with an arc or trajectory of a limb or a portion ofa limb.
 18. The method of claim 1, wherein the parameter associated withmotion of a part of the animal includes a magnitude and timing of jointangles.
 19. The method of claim 1, wherein the parameter associated withmotion of a part of the animal includes a flexion or extension of a limbor of a portion of a limb.
 20. The method of claim 1, wherein theparameter associated with motion of a part of the animal includes arange of limb motion.